This invention relates to a pedal operated assembly and more particularly to an improved signal mechanism for such an assembly.
In many forms of operator controlled devices it is either desirable or necessary to provide a signal in response to actuation of the device. For example, the brake assembly of a motor vehicle includes one or more signalling devices that provide a signal when the brakes are actuated. Such signals include the illumination of the brake lights and may also include a signal for deactivating a speed control unit, for deactivating a positive lock up in an automotive transmission and other similar, well known arrangements. Conventionally, it has been the practice to provide one or more switches having contact elements that are operated through engagement with a portion of the brake pedal assembly. The use of such separate switch contacts give rise to a number of functional and cost disadvantages. For exaple, it is necessary to insure that the switch is not actuated before the brake pedal is depressed but, nevertheless, the switch should be actuated immediately upon operation of the brake pedal. Due to the normal mounting environment, the relation and adjustment of the various switches associated with the brake pedal mechanism are complicated, cumbersome and difficult to adjust. Furthermore, these switches have a tendency to go out of adjustment in time and can provide either false signals or inadequate or unduly delayed signals. The safety hazards associated with either type of arrangement should be obvious.
In order to avoid the aforenoted difficulties, it has been proposed to locate the switch assembly directly at the brake pedal in such a manner that the switch is operated upon relative movement between the pedal pad and the more rigid element of the brake pedal. Such an arrangement is shown in U.S. Pat. No. 2,674,669, entitled Pedal Operated Braking System of Road Vehicles, issued Apr. 6, 1954 in the name of C. Leedam. Although such an arrangement may overcome certain of the aforenoted defects, this arrangement employs a contact that is associated with the brake pedal pad and a separate contact which is associated with the rigid plate of the brake pedal. Thus, the switch or signal device does not form a unitary assembly. As a result of this, tolerances must be very closely held and installation and assembly of the various components is critical. For this reason, an arrangement of the type shown in this patent has not enjoyed any commercial success.
It is, therefore, a principal object of this invention to provide an improved signal device for a pedal actuated mechanism which comprises a unitary assembly which is easy to install and which requires no adjustment upon installation.
It is another object of this invention to provide a signal device for a pedal operated system that is completely contained and sealed within the pedal pad assembly.
As has been previously noted, it is common in conjunction with vehicles embodying speed control devices to provide a speed control cut off switch that is actuated when the brakes are applied. Such units have the effect of disabling the speed control unit when the brakes are actuated. The purpose of such device is believed to be obvious. Due to the difficulties as aforenoted in adjusting and maintaining adjustment of the remotely positioned switches previously employed, and to guard against mechanical failures of the electrical circuit and switches associated with it, it may be desirable to provide a separate device which will also disable the throttle positioner associated with the speed control unit. Conventionally, such speed control units employ vacuum motors that function to position the throttle valve of associated engines. In order to provide a safety backup, it has been proposed to utilize a vacuum brake switch in the vacuum motor which will also disable the vacuum signal when the brakes are actuated. The previously proposed speed control vacuum interrupting devices have pneumatic valves that are remotely positioned and which must be independently adjustable. Such arrangements have the cost, function and installation disadvantages associated with the remotely positioned brake light switches.
It is, therefore, a still further object of this invention to provide a vacuum interrupting device that is associated directly with the brake pedal and which will be operated immediately upon actuation of the brake pedal.